package com.swak.frame.filter;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.lang3.StringUtils;

/**
 * 解决客服端跨越 问题
 * 
 * @author liuliang8
 *
 */
public class CorsFilter implements Filter {

    @Override
    public void destroy() {

    }

    @Override
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)
        throws IOException, ServletException {
        HttpServletResponse response = (HttpServletResponse) res;
        HttpServletRequest request = (HttpServletRequest) req;
        String origin = request.getHeader("origin");
        if (StringUtils.isBlank(origin)) {
            origin = "*";
        }

        response.setHeader("Access-Control-Allow-Origin", origin);
        response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
        response.setHeader("Access-Control-Max-Age", "3600");
        response.setHeader("Access-Control-Allow-Headers",
            " Origin, X-Requested-With, Content-Type, Accept");
        response.setHeader("Access-Control-Allow-Credentials", "true");
        /**
         * 处理cros 预请求
         */
        if (StringUtils.equalsIgnoreCase(request.getMethod(), "OPTIONS")) {
            response.setStatus(200);
        } else {
            chain.doFilter(req, res);
        }


    }

    @Override
    public void init(FilterConfig arg0) throws ServletException {

    }

}
